Study of CNTs and nanographite grown by thermal CVD using different precursors

Carbon nanotubes (CNTs) are obtained by chemical vapor deposition (CVD) on uncoated silicon and quartz substrates. The process of synthesis involves the co-evaporation of a carbon precursor and a metal catalyst in a nitrogen atmosphere in a high temperature furnace. Beside the formation of CNTs, by varying few parameters, other carbon structures can be deposited, such as a nanographite layer. In particular we believe that our version of thermalCVD is an economic and efficient process in alternative to other methods for the growth of nanographite. The morphology and structure of our samples were characterized by multi-wavelength Micro-Raman spectroscopy, SEM and HR-TEM analyses. We found that our CNTs have an average diameter of 80 nm, with length between few and hundreds of micrometers. Brunauer–Emmett–Teller (BET) analysis was used to calculate the specific surface area and porosity. Furthermore, we have performed an hydrogen storage experiment on our CNTs samples, finding an adsorption capacity of about 1.7 wt%, at 14 bar and 190 °C.